Polymer Jar Test Procedures

STANDARD JAR TEST PROCEDURE

The standard jar test is a critical procedure
for selecting the appropriate polymer for a aparticular clarification application.
This procedure allows individual polymers to be compared on such criteria
as floc formation, settling characteristics, and clarity. Generally, the
best performing products provide fast floc formation, rapid settling rate,
and clear supernatant. This test should be performed on-site, since large
amounts of water may be required for testing.

To save time, prepare the polymer test solutions
, between 12 and 24 hours in advance.

Required Equipment

Standard overhead stirrer/jar tester, preferably
with 6 stations and an illuminated base, beneath the beakers. Thomas Scientific sells
two different Phipps & Byrd models, which are updates to the
one Alken-Murray uses.

Beakers: 1 l.iter (1,000 mL) beaker (one
beaker per station on gang stirrer times the number of test runs with various
dilutions and competing polymers) You can purchase a box of 6 x 1 liter
beakers, with optimum price offered for purchase of a case of 4 boxes,
for a total of 24 x 1 liter beakers, sufficient for an active polymer laboratory.

Jars containing diluted Alken-Solutions
polymer at 0.1%, 0.5% and 1.0%. You can see from the table below that these
dilutions will allow you to apply treatment up to 20 mg/L in the sample
beaker.

Desired ppm ------>

0.25

0.5

1.0

2.0

3.0

5.0

10

20

Polymer Concentration

0.1%

0.25

0.5

1.0

2.0

3.0

*

*

*

0.5%

#

#

#

0.4

0.6

1.0

2.0

4.0

1.0%

#

#

#

#

#

0.5

1.0

2.0

Test Procedure

Check the total alkalinity and pH of the water
to be tested. Water containing an alkalinity of at least 25 mg/L and pH
of 7.0 will coagulate without adding alkaline salts. Color, as opposed to
turbidity can often be removed by lowering the pH as far as 6.0, by using
alum or an acid. Values higher than pH 7 may be helpful in removing manganese,
while still forming a floc.

Collect 5 gallon sample(s) of water to be
tested . This water should not have any polymer in it, however, it should
contain whatever substances that are typical of the system toi be treated.

Fill the 1,000 mL beakers with 1,000 mL
of samples. Place these on the gang stirrer..

Start the stirrer running at (80-100 rpm).

If the water system uses a primary coagulant,
such as polyaluminum chloride or ferric sulfate, this should be added,
here, to produce the concentration typical of the target system, UNLESS
you are testing the feasibility of substituting the polymer for the primary
coagulant.* Wait 30 seconds to 3 minutes.

Add Polymer solution, in the amounts determined
by the Dosage Chart, to each of the sample beakers, and mix for 30-60 seconds.

Observe and record rate of floc formation
and size of floc.

Stop the stirrer and allow samples to settle
for at least 5 minutes.

Observe the following:

Settling rate.

Floc separation (floating separate clumps)

Supernatant clarity.

Supernatant turbidity

Record data on appropriate form or spreadsheet
for later reference.

* Attempt to mimic actual system conditions.

CYLINDER SETTLING TEST

The floc formed in the Jar Test can be further
evaluated using this procedure. This method is also used for primary and
secondary clarifiers and sludge thickeners. Performance in this test is
evaluated on floc settling rate, sludge volume, and clarity of supernatant.

Required Equipment

Graduated cylinders 250 mL, as many as are
to be used for concurrent tests.